1. Field of the Invention
The present invention relates to a string clip positioning device of a racket string stretcher, and more particularly to a string clip positioning device of a racket string stretcher, wherein the string clip may be stopped and positioned efficiently.
2. Description of the Related Art
A conventional racket string stretcher in accordance with the prior art shown in FIG. 1 comprises a fixing seat xe2x80x9cAxe2x80x9d for fixing the racket, a base xe2x80x9cCxe2x80x9d, a string clip xe2x80x9cDxe2x80x9d, two slides 1xe2x80x2, two guide tracks 2xe2x80x2, two adjusting knobs 3xe2x80x2, and two stop press handles 4xe2x80x2. The slide 1xe2x80x2 may slide on the guide track 2xe2x80x2 to a determined position. Then, the adjusting knob 3+ may be rotated to fix the slide 1xe2x80x2. Then, the stop press handle 4xe2x80x2 may be pressed so that the string clip xe2x80x9cDxe2x80x9d may clip the string of the racket.
A conventional string clip positioning device for a racket string stretcher in accordance with the prior art shown in FIG. 2 comprises a disk 1 and a slide seat 2 mounted on the top and bottom of an elongated slot xe2x80x9cC1xe2x80x9d of the base xe2x80x9cCxe2x80x9d respectively, so that the slide 5 may be rotated freely and may slide in a rectangular track 3. The string clip 8 has a bottom provided with a shaft 7 that is mounted in a side end of the slide 5. A drive plate 6 is mounted in a bottom of the slide 5, and is pressed on a fulcrum 103 which is mounted on the top of the disk 1. A press rod 9 is mounted in the shaft 7, and is driven by a stop press handle 801 to press the drive plate 6. Thus, when the string clip 8 clips the string, the press rod 9 may be driven by the stop press handle 801 to press the drive plate 6 which presses the fulcrum 103, so that the bottom of the disk 1 may be urged on the top of the elongated slot xe2x80x9cC1xe2x80x9d of the base xe2x80x9cCxe2x80x9d, thereby stopping movement of the slide 5.
When the press rod 9 presses the drive plate 6, the relative pressure between the press rod 9 and the drive plate 6 may force the flange 703 on the bottom of the shaft 7 to rest the end face 501 of the slide 5, thereby producing a static friction, so as to position the string clip 8, thereby preventing the string clip 8 from being rotated freely. At the same time, the drive plate 6 may press the fulcrum 103 of the disk 1, thereby positioning and stopping movement of the slide 5. However, the press rod 9 and the fixing rod 4 apply a downward force on the drive plate 6, and the fulcrum 103 of the disk 1 applies an upward force on the drive plate 6, thereby bending the drive plate 6, so that the drive plate 6 is easily deformed plastically during long-term utilization.
A nut 402 mounted on the bottom of the fixing rod 4 may be rotated, or an adjusting screw 902 mounted on the bottom of the press rod 9 may be rotated (after some of the parts are disassembled), so as to adjust the tension of the drive plate 6. However, the drive plate 6 is easily worn out during long-term utilization.
The present invention has arisen to mitigate and/or obviate the disadvantage of the conventional string clip positioning device of a racket string stretcher.
The primary objective of the present invention is to provide a string clip positioning device of a racket string stretcher, wherein the string clip may be stopped and positioned efficiently.
Another objective of the present invention is to provide a string clip positioning device of a racket string stretcher, wherein the bearing wheel is rolled on the surface of the guide face of the push block, so that the bearing wheel will not be deformed plastically, thereby enhancing the efficiency of stopping and positioning the string clip.
A further objective of the present invention is to provide a string clip positioning device of a racket string stretcher, wherein when the bearing wheel is rubbed by the surface of the guide face of the push block, the adjusting bolt of the adjusting threaded rod may maintain the reliability of stopping and positioning the string clip.
In accordance with the present invention, there is provided a string clip positioning device of a racket string stretcher, comprising a slide seat, a pusher, a positioning member, and a track, wherein:
the track is formed with an elongated guide slot;
the slide seat is mounted on a top of the track, and has a first end formed with an insertion hole and a second end provided with a seat tube which has an upper portion formed with a mounting section and a lower portion formed with a receiving section communicating with the mounting section, the slide seat is formed with a chamber communicating with the insertion hole and the receiving section of the seat tube;
the positioning member is mounted on the first end of the slide seat, and includes a cap received in the insertion hole of the slide seat, and a clamping block mounted on a bottom of the track, the cap of the positioning member has an outer wall formed with a tapered bearing face, and has a bottom end provided with an insertion block received in the guide slot of the slide seat, the clamping block of the positioning member has a top end provided with a connecting block received in the guide slot of the slide seat;
a support shaft is pivotally mounted in the mounting section of the seat tube of the slide seat, and has a bottom formed with an annular flange which is rested on a top face of the receiving section of the seat tube of the slide seat;
a string clip is mounted on the support shaft, and includes a press handle, and a link pivotally connected with the pusher, so that the support shaft and the positioning member may be operated synchronously, so as to stop and position the string clip;
the pusher includes a push shaft movably mounted in the support shaft, the push shaft of the pusher has a top end pivotally connected with a first end of the link which has a second end pivotally connected with the press handle of the string clip, so that the push shaft of the pusher may be moved by the link which is moved by the press handle, the pusher includes a push block secured on a bottom end of the push shaft;
a follower is mounted in the chamber of the slide seat, and includes a bearing wheel, a wheel seat, an adjusting threaded rod, and a drive block, wherein:
the bearing wheel of the follower is rotatably mounted on a first end of the wheel seat of the follower and partially extended into the receiving section of the seat tube of the slide seat;
the drive block of the follower has a first end rested on a second end of the wheel seat of the follower, and a second end formed with a tapered drive end that may contact the bearing face of the cap of the positioning member; and
the adjusting threaded rod of the follower is screwed into the drive end of the drive block of the follower, and has a first end rested on the second end of the wheel seat of the follower.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.